selection: text_from_{clipboard,primary}: add 'done' callback

This callback is *always* called, including when there has been an
error.

This is in preparation for making text_from_{clipboard,primary}
asynchronous.

osc.c

@@ -102,6 +102,22 @@ from_clipboard_cb(const char *text, size_t size, void *user)
     free(chunk);
 }
 
+static void
+from_clipboard_done(void *user)
+{
+    struct clip_context *ctx = user;
+    struct terminal *term = ctx->term;
+
+    if (ctx->idx > 0) {
+        char res[4];
+        base64_encode_final(ctx->buf, ctx->idx, res);
+        term_to_slave(term, res, 4);
+    }
+
+    term_to_slave(term, "\033\\", 2);
+    free(ctx);
+}
+
 static void
 osc_from_clipboard(struct terminal *term, const char *source)
 {
@@ -124,27 +140,20 @@ osc_from_clipboard(struct terminal *term, const char *source)
     term_to_slave(term, &src, 1);
     term_to_slave(term, ";", 1);
 
-    struct clip_context ctx = {
+    struct clip_context *ctx = malloc(sizeof(*ctx));
-        .term = term,
+    *ctx = (struct clip_context) {.term = term};
-    };
 
     switch (src) {
     case 'c':
-        text_from_clipboard(term, term->wl->input_serial, &from_clipboard_cb, &ctx);
+        text_from_clipboard(
+            term, term->wl->input_serial,
+            &from_clipboard_cb, &from_clipboard_done, ctx);
         break;
 
     case 'p':
-        text_from_primary(term, &from_clipboard_cb, &ctx);
+        text_from_primary(term, &from_clipboard_cb, &from_clipboard_done, ctx);
         break;
     }
-
-    if (ctx.idx > 0) {
-        char res[4];
-        base64_encode_final(ctx.buf, ctx.idx, res);
-        term_to_slave(term, res, 4);
-    }
-
-    term_to_slave(term, "\033\\", 2);
 }
 
 static void

selection.c

@@ -566,17 +566,17 @@ selection_to_clipboard(struct terminal *term, uint32_t serial)
 void
 text_from_clipboard(struct terminal *term, uint32_t serial,
                     void (*cb)(const char *data, size_t size, void *user),
-                    void *user)
+                    void (*done)(void *user), void *user)
 {
     struct wl_clipboard *clipboard = &term->wl->clipboard;
     if (clipboard->data_offer == NULL)
-        return;
+        goto done;
 
     /* Prepare a pipe the other client can write its selection to us */
     int fds[2];
     if (pipe2(fds, O_CLOEXEC) == -1) {
         LOG_ERRNO("failed to create pipe");
-        return;
+        goto done;
     }
 
     int read_fd = fds[0];
@@ -609,10 +609,15 @@ text_from_clipboard(struct terminal *term, uint32_t serial,
             }
         }
 
-        cb(text, amount, user);
+        if (cb != NULL)
+            cb(text, amount, user);
     }
 
     close(read_fd);
+
+done:
+    if (done != NULL)
+        done(user);
 }
 
 static void
@@ -622,6 +627,15 @@ from_clipboard_cb(const char *data, size_t size, void *user)
     term_to_slave(term, data, size);
 }
 
+static void
+from_clipboard_done(void *user)
+{
+    struct terminal *term = user;
+
+    if (term->bracketed_paste)
+        term_to_slave(term, "\033[201~", 6);
+}
+
 void
 selection_from_clipboard(struct terminal *term, uint32_t serial)
 {
@@ -632,10 +646,8 @@ selection_from_clipboard(struct terminal *term, uint32_t serial)
     if (term->bracketed_paste)
         term_to_slave(term, "\033[200~", 6);
 
-    text_from_clipboard(term, serial, &from_clipboard_cb, term);
+    text_from_clipboard(
-
+        term, serial, &from_clipboard_cb, &from_clipboard_done, term);
-    if (term->bracketed_paste)
-        term_to_slave(term, "\033[201~", 6);
 }
 
 bool
@@ -696,21 +708,22 @@ selection_to_primary(struct terminal *term, uint32_t serial)
 
 void
 text_from_primary(
-    struct terminal *term, void (*cb)(const char *data, size_t size, void *user),
+    struct terminal *term,
-    void *user)
+    void (*cb)(const char *data, size_t size, void *user),
+    void (*done)(void *user), void *user)
 {
     if (term->wl->primary_selection_device_manager == NULL)
-        return;
+        goto done;
 
     struct wl_primary *primary = &term->wl->primary;
     if (primary->data_offer == NULL)
-        return;
+        goto done;
 
     /* Prepare a pipe the other client can write its selection to us */
     int fds[2];
     if (pipe2(fds, O_CLOEXEC) == -1) {
         LOG_ERRNO("failed to create pipe");
-        return;
+        goto done;
     }
 
     int read_fd = fds[0];
@@ -743,10 +756,15 @@ text_from_primary(
             }
         }
 
-        cb(text, amount, user);
+        if (cb != NULL)
+            cb(text, amount, user);
     }
 
     close(read_fd);
+
+done:
+    if (done != NULL)
+        done(user);
 }
 
 void
@@ -762,10 +780,7 @@ selection_from_primary(struct terminal *term)
     if (term->bracketed_paste)
         term_to_slave(term, "\033[200~", 6);
 
-    text_from_primary(term, &from_clipboard_cb, term);
+    text_from_primary(term, &from_clipboard_cb, &from_clipboard_done, term);
-
-    if (term->bracketed_paste)
-        term_to_slave(term, "\033[201~", 6);
 }
 
 #if 0

selection.h

@@ -29,9 +29,10 @@ bool text_to_clipboard(struct terminal *term, char *text, uint32_t serial);
 void text_from_clipboard(
     struct terminal *term, uint32_t serial,
     void (*cb)(const char *data, size_t size, void *user),
-    void *user);
+    void (*done)(void *user), void *user);
 
 bool text_to_primary(struct terminal *term, char *text, uint32_t serial);
 void text_from_primary(
-    struct terminal *term, void (*cb)(const char *data, size_t size, void *user),
+    struct terminal *term,
-    void *user);
+    void (*cb)(const char *data, size_t size, void *user),
+    void (*dont)(void *user), void *user);